how about giving it a customizable menu for say the colors a mesh takes on when selected, or the color of the grid lines or grid background. certain people might for instace find it hard to see the difference between light pink and dark pink easily. or the default black of unselected meshes.

This is it *exactly*. I have implemented (in tuhopuu now) a "skins" type project. All that is added are 6 possible types of buttons (Rounded Corner, Solid Corner, Gradient Background, etc), and the ability to customize the colours of (almost any) thing in blender. The Buttons, the buttons-background, the 3dview background, etc. Many people have asked for darker themes for blender, and this allows it, without making blender hugely slower. It even looks the same as current blender by default. So there is no problems if you like its current view. But, for people who find the current colours hard to work with, its dead easy to change now (instead of having to manually hack the source-code).